But something doesn't quite add up with this generalized warning, because an epidemic of melanoma has broken out among indoor workers. In fact, indoor workers get three to nine times LESS solar UV exposure than outdoor workers get, yet only indoor workers have increasing rates of melanoma - and the rates have been increasing since before 1940.
So what's really going on here with melanoma causes?
For point of discussion there are two primary types of UV rays from sunlight that you need to be concerned with: the vitamin D-producing UVB rays and the skin-damaging UVA light.
Both UVA and UVB can cause tanning and burning, although UVB does so far more rapidly. UVA, however, penetrates your skin more deeply than UVB, and may be a much more important factor in photo-aging, wrinkles, and skin cancers.
This latest study suggests that indoor workers may have increased rates of melanoma because they're exposed to sunlight through windows, and only UVA light, not UVB, can pass through window glass.
At the same time, these indoor workers are missing out on exposure to the beneficial UVB rays, and have lower levels of vitamin D. So it's the combination of exposure to UVA light and lower vitamin D levels that appears to be the most significant melanoma cause, and the indoor workers could clearly benefit from spending some time outdoors in the sun.
Why Optimal Sun Exposure Lowers Your Risk Of Cancer
Appropriate sun exposure actually helps prevent skin cancer. In fact, melanoma occurrence has been found to decrease with greater sun exposure, and can be increased by using sunscreens.
One such study discovered that melanoma patients with higher levels of sun exposure were less likely to die than other melanoma patients, and patients who already had melanoma and got a lot of sun exposure were prone to a less aggressive tumor type.
Why is this?
Dr. John Cannell, one of the leading authorities on vitamin D and founder and executive director of the Vitamin D Council, does an excellent job of explaining it in this video but to give you a summary: nature has devised a very clever strategy to keep the sun from damaging your skin.
It is important to realize that the sun can increase genetic damage in your skin and cause skin cancer, especially if you get regularly sunburned.
But what the media and many health "experts" fail to appreciate and explain to the public is that regular and safe exposure to sunlight or safe tanning beds allows vitamin D to be formed in your skin. The vitamin D then directly modulates genes in your skin that actually help prevent the types of abnormalities that ultraviolet light causes.
And it's not just melanoma that vitamin D helps protect you from. Optimizing your vitamin D levels can help you to prevent as many as 16 different types of cancer including pancreatic, lung, breast, ovarian, prostate, and colon cancers.
If You Wear Sunscreen, You Negate This Natural Cancer Protection
If you avoid the sun entirely, or slather on sunscreen whenever you go out, your skin will be unable to produce vitamin D, and you'll be left without this built-in cancer protection.
Further, for many years sunscreens only protected you from the beneficial UVB rays, while letting through skin-damaging UVA light. Even today, while most sunscreens do a good job blocking UVB, fewer filter out all of the UVA.
Not only that, but UVA rays are quite constant during ALL hours of daylight, throughout the year - unlike UVBs, which are low in the morning and evening, and high at midday.
So if you do decide to use sunscreen, make sure you choose one that is non-toxic and blocks both UVA and UVB rays. Two non-toxic ingredients that scatter both UVB and the more damaging UVA rays are titanium dioxide and zinc oxide. They've been used all over the world for more than 75 years as safe sunscreens.
However, keep in mind that you'll still need to spend time in the sun without any sunscreen at all in order to optimize your vitamin D levels.
The optimal time to be in the sun for vitamin D production is as near to solar noon as possible. That would be between roughly 10 a.m. and 2 p.m.
During this time you need the shortest exposure time to produce vitamin D because UVB rays are most intense at this time. Plus, when the sun goes down toward the horizon, the UVB is filtered out much more than the dangerous UVA.
This information is just beginning to permeate through the mainstream media, so let me repeat and emphasize this important point:
If you want to get out in the sun to maximize your vitamin D production, and minimize your risk of malignant melanoma, the middle of the day is the best and safest time to go.You just need to be very careful about the length of your exposure. Remember you only need enough exposure to have your skin turn the lightest shade of pink. This may only be a few minutes for some.
Once you reach this point your body will not make any additional vitamin D and any additional exposure will only cause harm and damage to your skin.
Most people with fair skin will max out their vitamin D production in just 10-20 minutes, or when your skin starts turning the lightest shade of pink. Some will need less, others more. The darker your skin, the longer exposure you will need to optimize your vitamin D production.
To learn more about sunlight and vitamin D, including why I recommend getting your levels tested and how to use the sun for cancer prevention, please set aside an hour to watch my free lecture on vitamin D.
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